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用基于Perzyna超应力理论与修正剑桥模型的简单的弹黏塑性本构模型,耦合比奥固结理论,来模拟堤坝荷载作用下的软土的速率效应特性.以土工织布加固的堤坝为实例,提出从最初几个加载阶段下的沉降数据来确定黏性参数的反分析法.根据反分析的参数值来模拟,同实测值予以比较,并同文献中使用其他四个不同本构模型的模拟结果进行比较,比较研究表明:本文建议的模型具有优越性.特别研究了土工织布加固对堤坝下软土的滞后变形和稳定性的影响.良好的模拟结果反应了所提出的反分析法的可用性,同时展示了所使用的弹黏塑性本构模型在岩土工程中的实用性:弥补了修正剑桥模型不能模拟速率效应特性的缺点;跟其他黏塑性本构模型比较,本模型参数确定方法简单,模拟结果准确.“,”The paper aims to model the rate-dependent behaviors of subsoil under embankment loads using a simple elasto-viscoplastic model, based on the modified Cam-clay model and Perzyna's overstress theory, coupled with Biot's consolidation theory. A geotextile reinforced embankment is studied. An inverse analysis procedure is proposed to identify the viscosity parameters of subsoil from the settlements due to the first few loading phases. In order to assess the performance of the proposed model, numerical predictions using the determined parameters are then compared with those obtained by four other models. Special attention is given to the effect of reinforcement on delayed deformations and on the stability of the embankments and foundations. The performance of the proposed inverse analysis procedure is also assessed. Finally, according to the simulation runs, it can be concluded that the proposed model is easy to be calibrated and suitable for geotechnical projects. The proposed model can describe the rate-dependent behaviors of soft soil compared with the modified Cam-clay model, with accuracy using the simple constitutive equations compared with other viscoplastic models.